Noun
twoness (countable and uncountable, plural twonesses)
The state or condition of being two; duality; doubleness.
One ever feels his twoness - an American, a Negro; two souls, two thoughts, two unreconciled strivings; two warring ideals in one dark body, whose dogged strength alone keeps it from being torn asunder. W. E. B. Du Bois
Students achieving Oneness will move on to Twoness. Woody Allen